Root extraction method and device

ABSTRACT

The invention relates to a method for extracting a root, whereby the root is extracted following a possible initial loosening of the root within the periodontal gap. A pin is inserted into the root and affixed there, whereafter a pulling element functionally linked with a tensioning device is connected with the pin. The pulling force required for extracting the root is subsequently applied to the root substantially in the direction of the axis of the tooth by means of the tensioning device that has been partially inserted into the mouth and supported there.

BACKGROUND OF THE INVENTION

The invention relates to a method for extracting a root, as well as adevice for applying the method.

In dental technology it is common that during the extracting of a toothand following the administering of a local anaesthetic, the root isfirst loosened somewhat inside the gum with a tool that is pushed intothe periodontal gap, and the tooth is then pulled out with plierstogether with the root. This does however become problematic if thetooth is broken or if the same is covered with a crown, wherepractically no grip surface is available for the pliers, and if only theroot alone is to be extracted.

It is the purpose of this invention to provide a method for the simpleextraction of a root and a device for applying the method.

SUMMARY OF THE INVENTION

This task is solved in accordance with the invention by a method and adevice for applying the method.

Further preferred embodiments of the method of this invention as well asthe device of this invention form the subject of the followingdescription.

A pin is inserted into the root and affixed there for extracting thesame. Then, a pulling element functionally linked with a manuallyactivatable tensioning device is inserted into the pin. Subsequently,the pulling force required for extracting the tooth is created andapplied to the root substantially in the axial direction of the same bymeans of the supported tensioning device partially inserted into themouth. Thus, a relative large pulling force can be applied to the rootwithout need of excessive force and without space problems and a risk ofpossible injury within the mouth. The device of this invention is simpleand cost-effective, and enables easy handling.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will now be explained with reference to the drawings,whereby:

FIG. 1 shows a longitudinal cross-section of an embodiment of a deviceof this invention for extracting a root;

FIG. 2 shows an overview of the device illustrated in FIG. 1;

FIG. 3 shows a cross-sectional view along the line III-III in FIG. 1;and

FIG. 4 shows a threaded pin as part of the device of this invention,with a counter piece for screwing the threaded pin into the root.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1 shows a device 1 for extracting a root, incorporating a pin 2that can be inserted into the root and affixed there, a pulling element3 that can be inserted into the pin 2, and a tensioning device 4functionally linked with the pulling element 3.

The pin 2 of the embodiment illustrated here takes the form of athreaded pin which is screwed into the tooth, root, preferably in thedirection of its axis. However, other means for affixing the pin 2 tothe tooth root could, be envisaged (this could, for example, consist ofa cement or adhesive connection or an expanding pin). In addition, theinsertion in the direction of the axis of the root is sometimes notpossible, or no longer possible, for example when the root is notstraight or is already equipped with one or two screws for the fittingof a crown.

The pin 2 is equipped with a bead 5, which is in turn equipped with ahook-shaped recess 6. As indicated in FIG. 4, the head 5 is preferablyequipped with an external shape (square) of the type that makes itpossible to screw a standardized adapter 7 into the root, onto which thehead 5 can be affixed.

The pulling element 3 already mentioned above is then hooked into thehook-shaped recess 6 with a cross pin 8. The pulling element 3 can, forexample, take the form of a flexible element such as a wire, a string,or a rope. At the other end of the pulling element 3, a cross pin 9 isalso provided, with which the pulling element 3 can be affixed to thetensioning device 4 as is described in more detail below.

The tensioning device 4 incorporates a stretched base body 10 which, inturn, has a guide groove 11 with a T-shaped cross section for atensioning support 12 that is longitudinally adjustable in relation tothe base body 10. A threaded bolt 15 extending in a longitudinaldirection has a front end 15 a screwed into the tensioning support 3.2,whereby a rear threaded part 15 b is guided through a support sleeve 16screwed onto the rear end of the base body 10 by means of screws 14. Aribbed nut 20 is provided on the threaded part 15 b, the same beingsupportable at a rear facing surface 17 of the support sleeve 16. Thetensioning support 12 can be supported in its longitudinal directionwith a rear surface 21 against a front facing surface 18 of the supportsleeve 16 on the one hand, and with a surface 22 located towards thefront against a front base body part 10 a on the other hand.

The tensioning support 12 is equipped with a number of hook-shapedrecesses 23 arranged on behind the other in longitudinal direction, ontowhich the pulling element 3 can be hooked with the cross pin 9. Adiverting part 24 for the pulling element 3 is affixed to the front basebody part 10 a. The pulling element 3 is held to extend substantially inan axial direction of the root in relation to the pin 3 on the one hand,and is also tensioned at a right angle to the axial direction of theroot in a longitudinal direction of the tensioning device 4 on the otherhand, and rests on the diverting part 24. The diverting part 24 takesthe form of a firmly affixed disc segment, the cross section of whichforms a guide nut 24 a for the pulling element 3, and the pullingelement 3 is affixed in a front side, fork-shaped part 25 of the frontbase body part 10 a by means of a cross pin 26.

On the side that faces away from the guide groove 11 for the tensioningsupport 12, the base body 10 is equipped with a groove 27 with adovetail cross-section (sec especially FIG. 3), into which a supportplate 28 made of plastic is inserted. The front base body section 10 aalso incorporates a groove 29 for receiving a rotating segment 30 asillustrated in FIG. 1 on the same side of the base body 10, and the axisof the segment 30 extends diagonally with respect to the displacementdirection of the tensioning support 12, and the segment 30 can beinserted from the side into the groove 29. The groove 29 forms the guidesurfaces for an external as well as an internal circumference surface 32of the rotating segment 30. For this, the groove 29 is placed in thefront base body section 10 a in such a way that the pulling elementextending to the pin 2 extends coaxially in relation to the rotatingsegment 30. The rotating segment 30 forms a cut-out defined by surfaces34, 35, whose alignment can be changed, i.e. adjusted by turning therotating segment 30. The rotating segment 30 is—much like the base body1.0 with the support plate 28—equipped with a support disc 38 made ofplastic, which is inserted into a groove 37 of the rotating segment 30with a dovetail cross-section (FIG. 1). The support plate 28 and thesupport disc 38 each have a resting surface 28 a, 38 a for supportingthe tensioning device 4 in the mouth.

When a root is to be extracted, the pin 2 is first inserted into theroot and affixed there, preferably screwed into the same. One end of thepulling element 3 is then inserted into (attached to) the pin 2, forexample by being hooked into the recess 6 with the cross pin 8, andaffixed to the tensioning device 4 that has been inserted into the mouthand is partially supported there with the other end. With the selectionof a suitable recess 23 for hooking therein the other cross pin 9, theposition of the location in the mouth that is to be treated (i.e., thedistance between the supporting point of the tensioning device in themouth and the root to be extracted) must be considered and a suitablepre-tensioning of the pulling element 3 created. The position of thetensioning support 12 between the front base body part 10 a and thefront facing surface 18 of the support sleeve 16 sets the startingposition prior to creating the actual pulling force for extracting theroot, and can also be quickly adjusted by means of axially adjusting theribbed nut 20 to suit the threaded part 15 b. With the rear surface 21of the tensioning support 12 abutting against the front facing surface18 of the support sleeve 16, the axial distance of the ribbed nut 20from the rear facing surface 17 of the support sleeve 16 determines thepath along which the tensioning support 12 can be quickly moved in alongitudinal direction without rotating the ribbed nut 20. The actualpulling force for extracting the root is then created by the ribbed nut20 abutting against the rear facing surface 17 of the support sleeve 16by turning the nut 20, and the subsequently created slow adjustment ofthe threaded part, i.e. tensioning support. For this, it is of advantagethat a relatively large pulling force can be created via the threadwithout excessive force. In addition, the diverting (directional change)of the pulling element 3 and the right-angled arrangement of thetensioning support 12 in relation to the pin 2 affixed onto the rootmeans that the root is pulled substantially in the direction of the axisof the root without creating space problems or a possible risk of injurywithin the mouth.

The support of the tensioning device 4 is carried out by means of thesupport surface 28 a of the support plate 28 (on the edge of the mouth)and via the support surface 38 a of the support disc 38 affixed to therotating segment 30 (for the location to be treated). The turnablerotating segment 30 can be adjusted to suit the relevant localconditions around the location that is to be treated in order toguarantee optimized support.

The fast adjustment of the tensioning support 12 already mentioned,which is limited in its maximum size by the abutment of the tensioningsupport 12 against the support sleeve 16 on one side, and by the frontbase body section 10 a on the other side, whereby the size can beadjusted (i.e. reduced by means of the ribbed nut 20) can also be usedfor pre-treating. In other words, the root can be loosened by areciprocal movement of the tensioning support to apply a sudden impactforce on the root prior to applying the actual pulling force. It is ofcourse also possible when required to carry out a loosening in theperiodontal gap by means of a suitable tool in the known way.

The device of this invention is simple and cost-effective, and enableseasy handling. The base body 10 of the tensioning device 4 can forexample be held with the thumb and middle finger of one hand, wherebythe index finger supports the positioning of the pulling element 3 onthe diverting part 24, and the ribbed nut 20 is activated with the otherhand. In principle, the pulling force could also be appliedmechanically.

It is possible to envisage means which effect a sudden impact upon thepulling element 3 during the turning of the ribbed nut 20. For example,the facing surface 17 of the support sleeve 16 and the ribbed nutabutting against the same 20 can be equipped with corresponding radiallyextending saw teeth or suchlike. During the turning of the ribbed nut,an additional increase can therefore be created across a certain angle,which is then decreased again.

1. A method of extracting a root of a tooth, comprising: inserting a pininto the root and affixing the pin to the root; connecting a flexiblepulling element to the pin affixed to the root by hooking the pullingelement into the pin, the pulling element comprising one of a wire, astring, or a rope bent at a substantially right angle along a divertingpart, the pulling element being functionally linked to a tensioningdevice; hooking the pulling element into the tensioning device;pre-tensioning the pulling element between the pin and the tensioningdevice before hooking the pulling element to the pin or the tensioningdevice; applying a pulling force to the root via the pulling elementusing the tensioning device so as to extract the root, wherein thepulling force is transmitted from a portion of the pulling element atthe diverting part to the root via the pulling element in a directionsubstantially parallel to the longitudinal axis of the root, and istransmitted from the tensioning device to the portion of the pullingelement at the diverting part via the pulling element in a directionsubstantially perpendicular to the longitudinal axis of the root, thetensioning device being partially inserted into and supported in themouth; wherein said pre-tensioning of the pulling element comprisesadjusting a tensioning support moveable substantially at a right anglein relation to the longitudinal axis of the root, the tensioning supportbeing adjustable in relation to a base body of the tensioning device;and loosening the root by sudden activation of the tensioning supportprior to said applying the pulling force to extract the root.
 2. Themethod of claim 1, wherein said applying the pulling force to extractthe root comprises turning a ribbed nut engaging a threaded boltconnected to the tensioning support, the threaded bolt being supportedon a base body.
 3. The method of claim 1, wherein said affixing the pinto the root comprises inserting a threaded pin into the root along thelongitudinal axis of the root.
 4. The method of claim 1, wherein saidconnecting the flexible pulling element to the pin comprises connectinga first end of the pulling element to the pin, a second end of thepulling element opposite the first end being functionally linked to thetensioning device, the diverting part being located between the firstend and the second end.
 5. The method of claim 1, further comprisinginitial loosening of the root within the periodontal gap before saidapplying the pulling force to extract the root.